The Journal of the American Medical Association (JAMA) has published the results of the IDEAL Study. The study enrolled 8888 patients under the age of 80 with a history of acute myocardial infarction and followed them up for a mean of 4.8 years after randomisation to Atorvastatin 80mg or Simvastatin 20mg.
The study was powered to compare these two lipid lowering strategies based on Major Coronary Endpoints. These included CHD Death, non-fatal MI and cardiac arrest with resuscitation.
The study did not reach statistical significance on the primary outcome. Looking at the three separate components of the primary outcome only non-fatal MI was significantly different (NNT of 83 over 4.8 years to prevent one event).
The study also reported on adverse effects and while overall the adverse effects were similar in the two groups, twice as many people in the Atorvastatin arm has treatment stopped (NNH of 18 over 4.8 years).
This study complicates the fire and forget vs treat to target debate. It seemed for a while that the evidence was starting to point to target based treatment. This study and perhaps the TNT Study might start to counter this evidence and point more towards a fire and forget approach. The TNT Study has been appraised in MeReC Extra 17.
In terms of preventing deaths, this study shows that Atorvastatin 80mg and Simvastatin 20mg are equivalent. There was a benefit in terms of non-fatal MI in the Atorvastatin arm, but would this have been as large or present at all if the comparator had been Simvastatin 40mg instead of 20mg?
Action: Clinicians can feel more confident in using Simvastatin 40mg as first line treatment for elevated cholesterol levels. The impact this study on the treat to target vs fire and forget debate will continue to be investigated.
References:
- High-Dose Atorvastatin vs Usual Dose Simvastatin for Secondary Prevention After Myocardial Infarction. JAMA 2005;294:2437-2445